pressure tendencypressure transducerpressurized conduitpressurized flowprevailing windpridictorprimary energyprimary openingprimary openingsprimary porposityprimary soilprimary tillageprimary waste managementprime agricultural landprincipal component analysisprinciple of additivity or superpositionprinciple of proportionalityprinciple of time invarianceprior analysisprismatic channelprobabability curveprobabilityprobability density functionprobability forecastprobable maximum floodprobeprobingproblem orientedproceduralprocedureprocedure orientedprocessprocess chartprocess orientedprocessingproductivity indexprofileprogradationprogramprogrammeprogressive waveprojectionprolangationprolangation operatorpropagationpropagation velocitypropeller anemometerpropeller typepropeller type current meterproper stocking